Tray-folding machine.



No. 830,294. PA'IENI'ED SEPT. 4, 1906. JOHN HAYS BIRCH & JOHN HENRY BIRCH.

TRAY FOLDING MACHINE.

APPLICATION IILHD MAY 27, 1905.

@mem/tow John Hays Birch .T 01m Eenry'Bimh ATENT FFICE.

JOHN HAYS BIRCH AND JOHN HENRY BIRCH, OF CRAWVFORDSVILLE, INDIANA.

TRAY-FOLDING MACHINE.

Specification of Letters Patent.

Patented Sept. 4, 1906.

Application filed May 27,1905. Serial No. 262,638.

T a/ZZ whom, it may concern:

Be it known that we, JOHN I-Iiirs BIRCH and JOHN HENRY BIRCH, citizens of the United States, residing at Crawfordsville, in the county of Montgomery and State of Indiana, have invented certain new and useful Improvements in Tray-Folding Machines, of which the following is a specification.

The object of our invention is to produce a folding means by which the box-trays may be folded at a single operation, the construction being such as to insure accuracy and squareness of fold, so that the sides of the tray will not bulge.

The accompanying drawings illustrate our invention.

Figure 1 is a central vertical section of our tray-forming mechanism in connection with adrying-wheel by means of which the folded trays may be held until the glue is sufficiently set. Fig. 2 is a plan of the parts shown in Fig. 1 Fig. 3, a perspective detail of a folding-lever and a part of its holder; Fig. 4, a perspective view of the foldinglever, and Fig. 5 is a plan of the blank from which the tray is formed.

In the drawings, 1() 10 indicate a pair of blocks which have formed in their adjacent faces vertical pockets 11 11, in each of which is pivoted a folding-lever 12. Each of said folding-levers is provided with an operatingarm 13, which lies below the axis of the lever, and a pair of folding-fingers 14 14, which are carried by the lever 12 at its ends.

Fitted in each pocket 1 1 on top ofthe contained folding-lever 12 is a yielding block or plate 15, the middle portion of which fills the space between the iingers 14 of the foldinglever. The block 15 is providedat its ends with projections 15', which project over the ingers 14, and its upper face is held even with the upper face of the block 10, in which it is mounted. The blocks 15 'are each supported by suitable guide-rods 16 and are urged inward into alinement with the vertical inner face of the containing block by means of suitable springs 17. Each folding-lever is normally held in the position indicated in Fig. 1 by means of a spring-plunger 18. The distance between the adjacent vertical faces of the two blocks is substantially equal to the external transverse dimension of the boxtray to be formed, and cooperating with the opening between these two blocksis a forming-plunger 20, the transverse dimension of .which is equal to the distance between the adjacent faces of the block 15, less approximately double the thickness of the material to be operated upon, and the longitudinal dimension of which is equal to the distance between the adjacent faces of the two fingers 14, less twice the thickness of the material operated on.

In operation the tray blanks are formed in any desired manner-such, for instance, by the machine described and claimed in our pending application, Serial No. 230,378. Each of these tray-blanks consists of a main body portion B, which forms the bottom of the tray, end flaps c, upon which are placed glue marks g, and sides 8, which terminate in side fiaps s. These blanks are fed to the space above the blocks 15 in any desired manner in succession beneath suitable guides 21, and as the plunger 2O descends the sides S are turned up by a downward movement of the plunger between the blocks 15, so as to lie between the sides of the plunger and the adjacent blocks 15, said blocks yielding to compensate for any variation in thickness of the material of the blank, but at all times holding the sides .s tightly against the plunger, so that the said tunity to buckle. The plunger descends until the bottom B of the tray is brought into engagement with the arms 13 of the folding-lever 12, whereupon further downward movement of the plunger causes the folding-levers to turn on their axes, and thus project the folding-'fingers 14 across the ends of the plunger 20, so as to fold the extended flaps s toward each other around the ends of the plunger. This operation takes place while the sides s are being held against buckle between the plunger and the blocks 13, so that a sharp square bend is made between the sides s and the flaps s. Further downward movement of the plunger brings its ends between the spring-pressed rollers 22, which thus operate to fold the end flaps c up and press them against the inturned flaps s', the glue strips g holding the parts in folded position. The formed tray is moving downward relative to the fingers 14 when the end flap e is being turned up, and in order to avoid gumming up the outside faces ol the l fingers 14 by the glue strips g the outer faces sides are held straight and given no opporof said fingers 14 are undercut, as at 14', so that the glue strips g will not come into contact with the ingers as the blank is forced downward between the spring-pressed rollers 22.- The plunger continues downward between the arms 13 of the folding-levers 12 and forces the tray into a radial pocket 25 formed in the drying-wheel, and as the formed tray passes down beyond the fingers 13 they are moved inward slightly by the plungers 18, so as to form stripping-fingers to prevent the upward movement of the formed tray when the plunger 2() is withdrawn. The plunger 2() moves downward until the formed tray is entirely inserted into the pocket 25, and. in order to facilitate the introduction of the formed trays into the drying-wheel we have found it desirableto provide the ends of each pocket with airchannels 27', which thus prevent the formation of any material pressure between two trays. The plunger 2O as it descends engages tne levers 12 comparatively close to the aXes thereof, so that the fingers'lfl, which extend radially a considerable distance greater than the point of contact of the plunger with the levers serve tov urge the fiaps s downward as well as toward each other, thus making a square bend and forcing the ends of the flap s towardthe bottom B, so that the edges of these flaps s will not stand above tne general plane of the top of the tray.

We claim as our invention- 1 In a tray-forming machine, the combinationl with a folding-plunger, of a pair of cooperating blocks arranged upon opposite sides of said plunger to engage the sides of the tray and nold them against the plunger, means for yieldingly urging said blocks in a right line squarely toward the sidesy of the plunger, means for engaging the projecting ends of said sides and folding them about the plunger while the sides of the tray remain between the plunger and the before-mentioned blocks, means covering said side endl folders, and other means for folding the end flaps about the lunger.

2. In a trayorming machine, the combination of a tray-forming plunger, -a pair of folding-levers arranged upon opposite sides of the path of movement of said plunger, each of said levers comprising an arm projecting into the path of movement of the plunger and a pair of fiap-folding fingers adapted to be projected to embrace the ends of the plunger, a pair of blocks each bridging the space between the flap-folding fingers of a folding-lever and extending over the flapfolding fingers and adapted to hold the sides of a tray against the sides of the plunger, and means for yieldingly urging each of said blocks in a right line squarely toward the plunger.

3. In a tray-forming machine, the combination of a tray-forming plunger, a pair of folding-levers arranged upon opposite sides of the path of movement of said plunger, each of said levers comprising an arm projecting into the path of movement of the plunger and a pair of flap-folding fingers adapted to be projected to embrace the ends ofthe plunger, means for normally holding said folding-levers with their flapengaging fingers in retracted position, a pair of blocks each bridging the space between and over the iap-folding fingers of a folding-lever and adapted to hold the sides of a tray against the sides of the plunger, and -rneans for yieldingly urging each of said blocks in a right line squarely toward the plunger.

'In witness whereof we have hereunto set our hands and seals, at Crawfordsville, Indiana, this 20th day of May, A. D. 1905.

JOHN HAYS BIRCH. [L. s] JOHN HENRY BIRCH. [L. s.] Witnesses: j

ROBERT H. WILLIAMS, STELLA WATTS. 

